Conventionally, photolithography technologies are used as the technologies to form fine patterns that are required for a semiconductor device, etc. However, miniaturization of such patterns becomes advanced and when a required process dimension becomes small to the wavelength of light or so used for an exposure, it becomes difficult for the photolithography technologies to cope with such miniaturization. Hence, instead of the photolithography technologies, electron beam lithography devices that are a kind of charged particle beam devices become nowadays popular.
The pattern formation using such electron beams applies a technique of directly drawing a mask pattern unlike one-shot exposure techniques using light sources, such as i rays and excimer laser, to form a pattern. The larger then number of the patterns to be drawn is, the more the exposure (lithography) time increases, and thus it takes a time to complete the drawing of patterns. Accordingly, together with the advancement of the integration degree of semiconductor integrated circuits, necessary time to form the patterns increases, which may decrease the throughput.
Accordingly, in order to speed-up the electron beam lithography devices, cell projection methods which combine masks in various shapes and which collectively emit electron beams to form patterns in a complex shape have been developed. However, together with the advancement of the miniaturization of the patterns, electron beam lithography devices become larger and larger, and the mask position control becomes further precise, resulting in the increase of the device costs.
In contrast, nano-imprinting technologies are known which form highly precise patterns at low costs. An example nano-imprinting technology is to push a stamper formed with concavities and convexities (a surface profile) corresponding to the concavities and convexities of a pattern to be formed against a transfer target obtained by, for example, forming a resin layer on a predetermined substrate, thereby forming a micro-pattern in the resin layer of the transfer target. Various applications of such nano-imprinting technologies are examined, such as formation of recording bit patterns in a large-capacity recording medium, and formation of semiconductor-integrated-circuit patterns.
Conventional hard stampers like silica used for the nano-imprinting technologies cannot cope with the warpage of a transfer-target substrate or a minute protrusion thereof at the time of transfer, and transfer-failed regions are produced in a broad range. In order to suppress the transfer-failed regions, it is necessary to cope with both warpage of the substrate and protrusion thereof. Hence, soft resin stampers have been examined which can cope with both warpage of the substrate and protrusion thereof (see Non-patent Literature 1). Moreover, there is an example report for a multi-layer resin stamper that has a soft resin layer called as a buffer layer and provided between the base material and the microstructure layer. Furthermore, in the nano-imprinting technologies, the peeling of the transfer target and the microstructure layer largely affects the transfer precision, the demolding performance of both transfer target and microstructure layer is very important. The conventional stampers like silica used for the nano-imprinting technologies are given with the demolding performance by processing a surface of the stamper with a fluorine-based demolding agent (see Patent Literature 1). The same process is applied to the surface of the soft stamper, and such a stamper is used for pattern transfer.